Anxiety is an occupational hazard, a fact of life, for professional traders. After all, even on good days, something is always going wrong, somewhere.

But when everything starts to go wrong at once, imaginations can run wild. Like now, when everywhere you look, something’s blowing up. In commodities, it’s the record plunge in oil. In equities, it’s six weeks of turbulence in the S&P 500. Debt markets have been rattled by the turmoil engulfing General Electric and PG&E. Bitcoin just plunged 13 percent. And Goldman Sachs, the storied investment bank, is having the worst week since 2016.

By themselves, none would be enough to incite panic. But have them erupt all around and even the most grizzled Wall Street types can start to sound paranoid. Does GE have something to do with Goldman? How does Bitcoin sway the stock market? Wildfires have nothing to do with crude’s convulsions, but both are bad news for banks.

“The risk of contagion is understood. What’s not understood is where and how connected things are,” Malcolm Polley, who oversees $1.2 billion as president of Stewart Capital Advisors LLC in Indiana, Pennsylvania, said by phone. “Just about anything can create panic, create contagion, and it doesn’t have to be something that makes sense.”

Semiconductors are the latest cause for hand-wringing after a batch of mediocre earnings. S&P 500 futures slid 0.7 percent Friday, while Nasdaq 100 contracts sank more than 1 percent as of 8:50 a.m. in New York.

In the global nervous system connecting modern markets, the synapses are misfiring. It started a month and a half ago in stocks, when the Nasdaq 100 began a streak of falling in 22 of 30 days. Then oil began to reel, ripping off 12 down days for the longest streak ever. GE, already down 20 percent by mid-October, has seen its shares go from above $13 to below $8, while its bonds kept plunging Thursday. A tumble in Goldman lopped $12 billion from its market cap.

That bad things should congregate isn’t surprising to Donald Selkin, chief market strategist at Newbridge Securities, who sees it as a consequence of having it so good for so long. He’s waking up every night to check the futures.

“People are saying, ‘Get me out across the board,”’ he said. “Everyone is anxious. I am anxious. You buy a good company and hope for the best and pray it doesn’t get destroyed. Look at Apple down $40. Look at some of the most well-known companies being decimated. I own Apple. I own Exxon. Of course I feel a lot of pressure.”

Maybe it’s going too far to say everything’s related. But it’s hard to argue that the shock of oil’s plunge isn’t rippling cross markets. As crude tumbled, energy producers became the biggest drag on global stocks. The blow landed in credit, where energy accounts for about 15 percent of the entire U.S. high-yield bond index.

Bitcoin is viewed as an isolated ecosystem but it does have a bearing on chipmakers, a particularly speculative corner of the market that is watched to gauge investors’ risk appetite. The digital currency’s peak in December came two months before the S&P 500’s worst rout in two years.

The connection between GE and banks? After the debt downgrade made it harder for the manufacturer to borrow through commercial paper, it has turned to credit lines provided by banks to fund businesses. According to its quarterly filings, the industrial conglomerate has drawn on $41 billion in credit lines from more than 30 lenders.

Not everyone is as gloomy. After fall, the growth rate of the economy and corporate profits is likely to stay positive for at least the next two years. If anything, the current market turmoil is likely to force the Federal Reserve to tone down monetary tightening and President Donald Trump to ease his combative stance on global trade, some strategists and investors say.

Stock investors are always throwing fits and for most of the last two months people have been able to point to corporate bonds as a market whose signals are both less dire and more relevant to global economic health. Indeed, credit spreads on investment-grade bonds largely stayed in a range in October even as the S&P 500 fell to the brink of a 10 percent correction.

“We have seen a number of idiosyncratic stories going on such as GE, GS, PG&E which are not necessarily a signal of a market correction,” said Dorian Garay, a money manager in New York at NN Investment Partners, which managed 240 billion euros as of June. “U.S. credit and macro fundamentals are solid as reiterated by recent macro indicators and earnings.”

Still, they haven’t been completely immune to conflagrations. The largest exchange-traded fund that buys high-yield debt has lost more than $1.5 billion this week, with short interest, as calculated by IHS Markit, ticking higher to 26 percent of shares outstanding.

Investors also soured on investment-grade companies, pulling money from iShares iBoxx $ Investment Grade Corporate Bond ETF for a second day, but piled into short-dated Treasuries, which are more insulated from rising rates and corporate defaults.

“We’re still focused not only on valuations but on the quality of balance sheets going forward,” said Joe Smith, deputy chief investment officer at Omaha, Nebraska-based CLS Investments, which manages $9 billion. Low rates have enabled borrowing to fund share repurchases and higher dividends, he added. “Some of those factors could likely translate as things that create more angst or anxiety for investors going forward as people start to think about whether those companies in effect overspent too much with their credit cards.”

The latest chain of blowups is in contrast with earlier this year, when money rotated from one place to another. Emerging markets in trouble? Investors found safety in U.S. equities. FANG stocks losing their shine? Park your money in oil or financial shares.

Fast forward to now and technology, energy and banks are taking turns leading the stock market lower. With the S&P 500 poised for one of the worst years since the bull market began in 2009, the concerted sell-off is ringing alarm bells for some. Is this the beginning of an end?

After one of the longest economic expansions in history, growth is bound to slow and the lack of leadership accentuates investor worries that no one is immune to the cycle. And a lot of them are ready to bail at the first sign of danger.

At the back of many minds is the idea that buy-side forces -- investment funds in trouble -- are behind the chaos. “Crowded trades” has become a buzzword in stocks, where companies with the highest ownership by professional speculators fell twice more than those with the lowest in October. Frantic selling by investment banks that wrote hedges has been implicated in oil’s collapse.

“You get a sense that hedge fund books are moving around,” said Andrew Hopkins, who helps oversee $88 billion as head of equity research at Wilmington Trust Co. While Hopkins is confident fundamentals will reassert themselves and calm everything down, “we’ve got some weakness and people are reacting to that weakness and think this is the end,” he said.

Anxiety is an occupational hazard, a fact of life, for professional traders. After all, even on good days, something is always going wrong, somewhere.But when everything starts to go wrong at once, imaginations can run wild.